Managing on-demand email storage

ABSTRACT

A method, system, and program for managing on-demand email storage are provided. An email service provider allocates a predetermined amount of storage space to an intended recipient. When an email is received for the intended recipient at the email service provider, the email service provider determines whether the predetermined storage space has sufficient capacity for storage of the email. If the predetermined storage space is insufficient for storage of the email, then the email service provider allocates on-demand storage space to the intended recipient. The email service provider then stores the email in the on-demand storage space, such that the email is stored, rather than discarded, when the predetermined storage space reaches full capacity. Before allocating on-demand storage space, the email service provider may compare the email characteristics with predefined criteria set by the intended recipient for emails to be stored in on-demand storage space.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates in general to improved messaging systemsand in particular to improved filing of electronic messages withinmessaging systems. Still more particularly, the present inventionrelates providing and managing on-demand email storage space, such thatimportant emails can be stored, rather than discarded, when thepre-determined email storage space is full.

2. Description of the Related Art

The use of electronic mail (email) and other electronic messaging andcommunications, such as instant messaging, has expanded rapidly over thelast few years. Typically, an email application, such as Lotus™ Notes,provides a user interface between the user and an email server thatsends and receives email via a network, such as the Internet.

An email server is typically hosted by an Internet Service Provider(ISP) or other entity that hosts email services. Each ISP typicallypre-defines the amount of disk space each user is allowed for holdingemail and attachments. Some ISPs will provide free email service, withminimal disk space, but accessibility from any computer system. OtherISPs may charge a monthly fee for email access. Further still, some ISPsmay provide sufficient disk space, but are accessible only from a systemlogged into an Intranet.

Regardless of the disk space allowed, when a user's disk space is full,ISPs begin to toss emails, rather than store emails for the intendedrecipient. To free disk space, users must monitor emails and eithertransfer emails to a local storage system or delete emails.

Discarding all emails once disk capacity is full is not preferable formany users. In particular, while a user may receive many “junk” emailsduring the day, the user may also receive many important emails that theuser does not want just discarded.

In view of the foregoing, it would be advantageous to provide a method,system, and program, for enabling a mail user to request on-demandstorage capacity, when the predetermined email storage space is full,such that incoming emails that are of importance to the user are stored,rather than discarded. Further, it would be advantageous to provide amethod, system, and program for managing on-demand storage, such that auser is only billed for the additional storage capacity temporarilyreceived.

SUMMARY OF THE INVENTION

Therefore, the present invention provides improved messaging systems andin particular provides for improved filing of electronic messages withinmessaging systems. Still more particularly, the present inventionprovides a method, system, and program for managing on-demand emailstorage space, such that important emails can be stored, rather thandiscarded, when the pre-determined email storage space is full.

According to one aspect of the invention, an email service providerallocates a predetermined amount of storage space to an intendedrecipient. When an email is received for the intended recipient at theemail service provider, the email service provider determines whetherthe predetermined storage space has sufficient capacity for storage ofthe email. If the predetermined storage space has insufficient capacityfor storage of the email, then the email service provider allocateson-demand storage space to the intended recipient. The email serviceprovider then stores the email in the on-demand storage space, such thatthe email is stored, rather than discarded, when the predeterminedstorage space reaches full capacity. The email service provider tracksuse of on-demand storage space and may charge the intended recipient forthe use of on-demand storage space.

According to another aspect of the invention, when the email serviceprovider determines that the predetermined storage space hasinsufficient capacity for storage of the email, then the email serviceprovider determines whether the intended recipient is registered for theon-demand storage space. If the intended recipient is registered foraddition of on-demand storage space, then the on-demand storage space isallocated to the intended recipient. However, if the intended recipientis not registered for the on-demand storage space, then the emailservice provider discards the email.

According to yet another aspect of the invention, when the email serviceprovider determines that the predetermined storage space hasinsufficient capacity for storage of the email, then the email serviceprovider determines whether the characteristics of the email matcheswith criteria set by the intended recipient for use of on-demand storagespace. The criteria may include, an email identifier, a domain name, anemail size, and a keyword, for example. If the characteristics of theemail match the criteria, then the email service provider allocates theon-demand storage space to the intended recipient. If thecharacteristics of the email do not match the criteria, then the emailservice provider discards the email.

Following, an intended recipient, or email subscriber, is promptedthrough a user interface to select whether to access on-demand storagespace when the predetermined storage space is full. If the intendedrecipient selects to access on-demand storage space, then the intendedrecipient is also prompted to select criteria to determine which emailsare important enough to the intended recipient that on-demand storagespace should be allocated. The on-demand storage space selection andcriteria selections are stored by the mail service provider such thatwhen the intended recipient predetermined storage space has insufficientcapacity for storage of an email, the email service provider is enabledto determined whether to allocate on-demand storage space for theparticular email.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features believed characteristic of the invention are setforth in the appended claims. The invention itself however, as well as apreferred mode of use, further objects and advantages thereof, will bestbe understood by reference to the following detailed description of anillustrative embodiment when read in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a block diagram depicting a computer system in which thepresent method, system, and program may be implemented;

FIG. 2 depicts a distributed network system for facilitatingdistribution of electronic messages between a sender and a recipientthrough an email service provider;

FIG. 3 depicts a block diagram of an email service provider server inaccordance with the method, system, and program of the presentinvention;

FIG. 4 depicts an example of types of information included in recipienton-demand criteria;

FIG. 5 depicts an example of entries in an on-demand charges database;

FIG. 6 depicts a pictorial representation of an email storage systemwith on-demand storage capacity in accordance with the method, system,and program of the present invention;

FIG. 7 depicts a graphical user interface for prompting a registeredrecipient to register for on-demand message storage services; and

FIG. 8 depicts a high level logical flowchart of a process and programfor managing on-demand email storage in accordance with the method,system, and program of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings and in particular to FIG. 1, there isdepicted one embodiment of a system through which the present method,system, and program may be implemented. The present invention may beexecuted in a variety of systems, including a variety of computingsystems and electronic devices.

Computer system 100 includes a bus 122 or other communication device forcommunicating information within computer system 100, and at least oneprocessing device such as processor 112, coupled to bus 122 forprocessing information. Bus 122 preferably includes low-latency andhigher latency paths that are connected by bridges and adapters andcontrolled within computer system 100 by multiple bus controllers. Whenimplemented as a server system, computer system 100 typically includesmultiple processors designed to improve network servicing power.

Processor 112 may be a general-purpose processor such as IBM's PowerPC™processor that, during normal operation, processes data under thecontrol of operating system and application software accessible from adynamic storage device such as random access memory (RAM) 114 and astatic storage device such as Read Only Memory (ROM) 116. The operatingsystem preferably provides a graphical user interface (GUI) to the user.In a preferred embodiment, application software contains machineexecutable instructions that when executed on processor 112 carry outthe operations depicted in the flowchart of FIG. 8, and other operationsdescribed herein. Alternatively, the steps of the present inventionmight be performed by specific hardware components that containhardwired logic for performing the steps, or by any combination ofprogrammed computer components and custom hardware components.

The present invention may be provided as a computer program product,included on a machine-readable medium having stored thereon the machineexecutable instructions used to program computer system 100 to perform aprocess according to the present invention. The term “machine-readablemedium” as used herein includes any medium that participates inproviding instructions to processor 112 or other components of computersystem 100 for execution. Such a medium may take many forms including,but not limited to, non-volatile media, volatile media, and transmissionmedia. Common forms of non-volatile media include, for example, a floppydisk, a flexible disk, a hard disk, magnetic tape or any other magneticmedium, a compact disc ROM (CD-ROM) or any other optical medium, punchcards or any other physical medium with patterns of holes, aprogrammable ROM (PROM), an erasable PROM (EPROM), electrically EPROM(EEPROM), a flash memory, any other memory chip or cartridge, or anyother medium from which computer system 100 can read and which issuitable for storing instructions. In the present embodiment, an exampleof a non-volatile medium is mass storage device 118 which as depicted isan internal component of computer system 100, but will be understood toalso be provided by an external device. Volatile media include dynamicmemory such as RAM 114. Transmission media include coaxial cables,copper wire or fiber optics, including the wires that comprise bus 122.Transmission media can also take the form of acoustic or light waves,such as those generated during radio frequency or infrared datacommunications.

Moreover, the present invention may be downloaded as a computer programproduct, wherein the program instructions may be transferred from aremote computer such as a server 140 to requesting computer system 100by way of data signals embodied in a carrier wave or other propagationmedium via a network link 134 (e.g. a modem or network connection) to acommunications interface 132 coupled to bus 122. Communicationsinterface 132 provides a two-way data communications coupling to networklink 134 that may be connected, for example, to a local area network(LAN), wide area network (WAN), or directly to an Internet ServiceProvider (ISP). In particular, network link 134 may provide wired and/orwireless network communications to one or more networks.

Network link 134 in turn provides data communication services throughnetwork 102. Network 102 may refer to the worldwide collection ofnetworks and gateways that use a particular protocol, such asTransmission Control Protocol (TCP) and Internet Protocol (IP), tocommunicate with one another. Network link 134 and network 102 both useelectrical, electromagnetic, or optical signals that carry digital datastreams. The signals through the various networks and the signals onnetwork link 134 and through communication interface 132, which carrythe digital data to and from computer system 100, are exemplary forms ofcarrier waves transporting the information.

When implemented as a server system, computer system 100 typicallyincludes multiple communication interfaces accessible via multipleperipheral component interconnect (PCI) bus bridges connected to aninput/output controller. In this manner, computer system 100 allowsconnections to multiple network computers.

In addition, computer system 100 typically includes multiple peripheralcomponents that facilitate communication. These peripheral componentsare connected to multiple controllers, adapters, and expansion slotscoupled to one of the multiple levels of bus 122. For example, an audiooutput device 128 and audio input device 129 are connectively enabled onbus 122 for controlling audio outputs and inputs. A display device 124is also connectively enabled on bus 122 for providing visual, tactile orother graphical representation formats and a cursor control device 130is connectively enabled on bus 122 for controlling the location of apointer within display device 124. A keyboard 126 is connectivelyenabled on bus 122 as an interface for user inputs to computer system100. In alternate embodiments of the present invention, additional inputand output peripheral components may be added.

Those of ordinary skill in the art will appreciate that the hardwaredepicted in FIG. 1 may vary. Furthermore, those of ordinary skill in theart will appreciate that the depicted example is not meant to implyarchitectural limitations with respect to the present invention.

With reference now to FIG. 2, a block diagram depicts a distributednetwork system for facilitating distribution of electronic messagesbetween a sender and a recipient through an email service provider.Distributed data processing system 200 is a network of computers inwhich one embodiment of the invention may be implemented. It will beunderstood that the present invention may be implemented in otherembodiments of systems enabled to communicate via a connection.

In the embodiment, distributed data processing system 200 containsnetwork 102, which is the medium used to provide communications linksbetween various devices and computers connected together withindistributed data processing system 200. Network 102 may includepermanent connections such as wire or fiber optics cables, temporaryconnections made through telephone connections and wireless transmissionconnections.

In the depicted example, email service provider server 204 is connectedto network 102. In addition, client systems, herein termed as sendersystem 208 and recipient system 210, are connected to network 102 andprovide a user interface through input/output (I/O) devices. Emailservice provider server 204 may facilitate electronic messaging systemsthrough which sender system 208 and recipient system 210 communicatethrough messaging applications, such as a mail reader, located on sendersystem 208 and recipient system 210. Messaging applications residing onsender system 208 and recipient system 210 provide an interface forimplementing messaging services on sender system 208 and recipientsystem 210. Further, distributed data processing system 200 may includeadditional servers, clients, and other devices not shown. For example,electronic messages may be sent and received between email serviceprovider server 204 and other servers (not shown) to distribute andreceive messages from sender system 208, recipient system 210, and otherclients (not shown).

The client/server environment of distributed data processing system 200is implemented within many network architectures. In one example,distributed data processing system 100 is the Internet with network 102representing a worldwide collection of networks and gateways that usethe TCP/IP suite of protocols to communicate with one another. TheInternet is enabled by millions of high-speed data communication linesbetween major nodes or host computers. In another example, distributeddata processing system 200 is implemented as an intranet, a local areanetwork (LAN), or a wide area network (WAN). Moreover, distributed dataprocessing system 200 may be implemented in networks employingalternatives to a traditional client/server environment, such as a gridcomputing environment.

Within distributed data processing system 200, each of client systems208 and 210 and email service provider server 204 may function as both a“client” and a “server” and may be implemented utilizing a computersystem such as computer system 100 of FIG. 1. Further, while the presentinvention is described with emphasis upon email service provider server204 facilitating the transfer of electronic messages, the presentinvention may also be performed by clients 208 and 210 engaged inpeer-to-peer network communications and downloading via network 102.

According to one embodiment, sender system 208 sends an email intendedfor the recipient at recipient system 210. The email is directed throughnetwork 102 to email service provider server 204, where email serviceprovider server 204 facilitates the email service for the registeredrecipient at recipient system 210. Email service provider serverpreferably allocates a predetermined amount of storage space eachregistered recipient for storing emails. Recipient system 210 preferablyconnects to email service provider server 204 and periodically requestscopies of the email stored for the recipient by email service providerserver 204.

When the storage space for a registered recipient has insufficientcapacity to store a new email, email service provider service 204 mayallocate on-demand messaging storage space to the registered recipientfor storage of the new email. Otherwise, email service provider server204 will discard the message.

In addition to registering for email service, recipients preferablyregister with email service provider server 204 to receive the on-demandemail storage service. Email service provider server 204 may implementrecipient system 210 as a user interface for prompting registration forthe on-demand email storage service. Alternatively, a systemadministrator or automated system may register a recipient for theon-demand email storage service.

In addition, when an intended recipient registers for the on-demandemail storage service, the intended recipient may also be prompted toselect criteria that will specify the types of email that are importantto the intended recipient for on-demand messaging storage. An intendedrecipient is also preferably provided with the cost per use of on-demandmessaging storage.

Advantageously, by email service provider server 204 allowing registeredrecipients to pre-select on-demand storage service, email serviceprovider server 204 is enabled to increase revenue based on user need.Further, advantageously, by email service provider server 204 managingon-demand message storage, registered recipients are provided with theoption to ensure that important emails are received even when apre-determined message storage system is full.

It is important to note that while email service provider server 204 isdescribed with emphasis upon the email service provided, email serviceprovider server 204 may also serve as a general ISP or other type ofservice provider. In addition, it is important to note that while thepresent invention is described with emphasis upon email storage ordiscarding, other types of electronic messages may also be stored inon-demand storage when a mailbox capacity for storing electronicmessages is full. Further, it is important to note that email includesthe header, text, and any attachments associated with an email.

Referring now to FIG. 3, there is depicted a block diagram of an emailservice provider server in accordance with the method, system, andprogram of the present invention. As depicted, email service providerserver 204 includes an email storage system 302. Preferably, emailstorage system 302 includes multiple data storage systems in which emailmessages intended for registered recipients are stored. The physicalstorage systems are preferably logically arranged into multiplepartitions, where each partition is designated for emails from adifferent registered recipient. Each registered recipient is preferablyassigned a specified size of storage space from email storage system302. For example, a registered recipient may be assigned 20 MB ofstorage space for storage of incoming email intended for the registeredrecipient.

In addition, email service provider server 204 includes an email storagecontroller 306. Email storage controller 306 detects each new emailmessage received at mail server provider server 204 and parses each newemail message to determine the intended registered recipient. Next,email storage controller 306 determines whether the registered recipientstorage space has sufficient capacity to store the new email. If thestorage space does not have sufficient capacity to store the new email,then email storage controller 306 determines whether the registeredrecipient has registered for the on-demand messaging storage service.Recipient on-demand criteria 304 designates which registered recipienthave specified on-demand service and the criteria for invoking theon-demand service. If the characteristics of the email meet recipienton-demand criteria 304, then email storage controller 306 allocatesadditional storage space to the registered recipient and stores theemail in the additional storage space. In addition, email storagecontroller 306 updates on-demand charges database 308 with eachallocation of on-demand capacity to a registered recipient. Emailstorage controller 306 discards the email.

With reference now to FIG. 4, there is depicted an example of types ofinformation included in recipient on-demand criteria. As illustrated,recipient on-demand criteria 304 includes multiple types of information.First, a recipient identifier (ID) indicates the registered emailaddress for each recipient. Next, for each recipient ID, a designator ofwhether the registered recipient has pre-selected the on-demand serviceis indicated.

The registered recipient may also specify the dates and times foron-demand service. In the example, the date of service is identified asparticular days in May, however in alternate embodiments, a registeredrecipient may specify other time periods, such as a particular day ofthe week, time of day, or other time period.

A cost per MB of on-demand service negotiated with the registeredrecipient is also recorded. In addition to a cost per MB, other units ofmeasurement may be negotiated for the cost of on-demand services. It isimportant to note that when on-demand storage space is allocated to anintended recipient it is preferably temporary storage space such thatthere may be a cost associated with keeping the on-demand storage spaceafter the email stored therein is read or other criteria.

The registered recipient may specify characteristics of emails for whichon-demand capacity should be added. In the example, sender addresses,sender domains, and topics (re:) for which on-demand capacity should beadded are specified. It will be understood that other emailcharacteristics may be specified. For example, a user may specify amaximum size of an attachment or specify that the email, but not theattachment, should be stored when on-demand capacity is allocated forthe email.

Referring now to FIG. 5, there is depicted an example of entries in anon-demand charges database. As depicted, examples of entries forrecipient “janemore” in on-demand charges database 308 specify thecharacteristic satisfied for the on-demand charge and the cost of thecharge. In addition, a total cost for on-demand capacity for theregistered recipient is depicted. It will be understood that additionalinformation may be recorded for each on-demand charge including, but notlimited to, date of receipt, size of email, and other characteristics.

With reference now to FIG. 6, there is depicted a pictorialrepresentation of an email storage system with on-demand storageavailable in accordance with the method, system, and program of thepresent invention. As depicted, a storage volume 600 is partitioned intospecific sizes of disk storage space for each recipient. For example,recipient “janemore” and recipient “tomallen” are each allocated 20 MBof storage space and actually use 19.5 MB and 15 MB respectively.Recipient “samman” is allocated 8 MB of storage space. Further, 50 MB ofstorage space are available for on-demand allocation. It will beunderstood that each recipient may receive a different amount of diskstorage space.

In the example, a new email 610 is received for recipient “janemore”.Predetermined storage space 604 for “janemore” only has 0.5 MBremaining. Since new email 610 is 1 MB in size, predetermined storagespace 604 has insufficient capacity for storage of new email 610.Referring to recipient on-demand criteria 304 of FIG. 4, recipient“janemore” is registered for on-demand message storage. Next, when thecharacteristics of new email 610 are compared with recipient on-demandcriteria 304, the sender domain of new email 610 matches a recipientspecified sender domain in criteria 304. As a result, the email storagecontroller preferably allocates 1 MB of disk space from on-demandstorage 606 to recipient “janemore” as indicated at reference numeral602. Then, new email 610 is stored in the allocated on-demand storageindicated at reference numeral 602. Although not depicted, the diskspace allocated at reference numeral 602 may be added to a logicalpartition of storage space allocated to recipient “janemore”.

It is important to note that on-demand storage 606 may be storage spacespecifically designated for on-demand requests. Alternatively, on-demandstorage 606 may be the storage space not currently used by intendedrecipients to whom it is allocated. Further, on-demand storage 606 maybe accessed from other storage systems accessible via a network or froma dedicated on-demand storage system.

Referring now to FIG. 7, there is depicted a graphical user interfacefor prompting a registered recipient to register for on-demand messagestorage services in accordance with the method, system, and program ofthe present invention. As depicted, an on-demand message user interface700 is a graphical user interface which may be displayed on a displaydevice, such as display device 124 of FIG. 1. In the example interface,a user may make selections with an input device, such as cursor 702,through which a user may select “yes” to pre-select the on-demandmessage storage service and may select to specify criteria such as mailidentifiers (IDs), domain names, email size, times, and keywords.

With reference now to FIG. 8, there is depicted a high level logicalflowchart of a process and program for managing on-demand email storagein accordance with the method, system, and program of the presentinvention. As depicted, the process starts at block 800 and thereafterproceeds to block 802. Block 802 depicts a determination whether a newemail is received for a registered recipient. If a new email is notreceived for a registered recipient, then the process iterates at block802. If a new email is received for a registered recipient, then theprocess passes to block 804. Block 804 depicts a determination whetherthe recipient's mail storage space has capacity sufficient for storingthe email. If the recipient's storage space has sufficient capacity,then the process passes to block 814. Block 814 depicts storing theemail in the recipient mail storage space, and the process ends.

Returning to block 804, if the recipient's mailbox capacity is notsufficient for storing the email, then the process passes to block 806.Block 806 depicts a determination whether the recipient has pre-selectedon-demand message storage. If the recipient has not pre-selectedon-demand message storage, then the process passes to block 816. Block816 depicts discarding the email, and the process ends. Otherwise, atblock 806, if the recipient has pre-selected on-demand message storage,then the process passes to block 808. Block 808 depicts a determinationwhether the email characteristics match the on-demand criteria set bythe recipient. If the email characteristics do not match the on-demandcriteria, then the process passes to block 816 and the email isdiscarded. If the email characteristics do match the on-demand criteria,then the process passes to block 810. Block 810 depicts allocatingon-demand storage space for the recipient. Next, block 812 depictsstoring the email in the allocated on-demand storage space, and theprocess ends.

While the invention has been particularly shown and described withreference to a preferred embodiment, it will be understood by thoseskilled in the art that various changes in form and detail may be madetherein without departing from the spirit and scope of the invention.

1. A method for managing on-demand email storage, comprising: receivingan email for an intended recipient at an email service provider, whereina predetermined storage space is allocated to said intended recipient bysaid email service provider; determining whether said predeterminedstorage space has sufficient capacity for storage of said email;responsive to determining said predetermined storage space hasinsufficient capacity for storage of said email, allocating on-demandstorage space to said intended recipient; and storing said email in saidallocated on-demand storage space, such that said email is stored,rather than discarded, when said predetermined storage space reachesfull capacity.
 2. The method according to claim 1 for managing on-demandemail storage, wherein allocating on-demand storage space to saidintended recipient further comprises: determining, responsive todetermining said predetermined storage space has insufficient capacityfor storage of said email, whether said intended recipient is registeredfor said on-demand storage space; responsive to determining saidintended recipient is registered for said on-demand storage space,allocating on-demand storage space to said intended recipient; andresponsive to determining said intended recipient is not registered forsaid on-demand storage space, discarding said email.
 3. The methodaccording to claim 1 for managing on-demand email storage, whereinallocating on-demand storage space to said intended recipient furthercomprises: determining, responsive to determining said predeterminedstorage space has insufficient capacity for storage of said email,whether said email matches with criteria set by said intended recipientfor addition of said on-demand storage space; responsive to said emailmatching said criteria, allocating on-demand storage space to saidintended recipient; and responsive to said email not matching saidcriteria, discarding said email.
 4. The method according to claim 3 formanaging on-demand email storage, wherein said criteria comprises atleast one from among an email identifier, a domain name, an email size,and a keyword.
 5. The method according to claim 1 for managing on-demandemail storage, further comprising: charging said intended recipient forsaid allocated on-demand storage space.
 6. A system for managingon-demand email storage, comprising: an email service provider systemcommunicatively connected to a network, wherein a predetermined storagespace is allocated to said intended recipient by said email serviceprovider system; said email service provider system further comprising:means for receiving an email for an intended recipient at an emailservice provider; means for determining whether said predeterminedstorage space has sufficient capacity for storage of said email; means,responsive to determining said predetermined storage space hasinsufficient capacity for storage of said email, for allocatingon-demand storage space to said intended recipient; and means forstoring said email in said allocated on-demand storage space, such thatsaid email is stored, rather than discarded, when said predeterminedstorage space reaches full capacity.
 7. The system according to claim 6for managing on-demand email storage, wherein said means for allocatingon-demand storage space to said intended recipient further comprises:means for determining, responsive to determining said predeterminedstorage space has insufficient capacity for storage of said email,whether said intended recipient is registered for said on-demand storagespace; means, responsive to determining said intended recipient isregistered for said on-demand storage space, for allocating on-demandstorage space to said intended recipient; and means, responsive todetermining said intended recipient is not registered for said on-demandstorage space, for discarding said email.
 8. The system according toclaim 6 for managing on-demand email storage, wherein said means forallocating on-demand storage space to said intended recipient furthercomprises: means for determining, responsive to determining saidpredetermined storage space has insufficient capacity for storage ofsaid email, whether said email matches with criteria set by saidintended recipient for addition of said on-demand storage space; means,responsive to said email matching said criteria, for allocatingon-demand storage space to said intended recipient; and means,responsive to said email not matching said criteria, for discarding saidemail.
 9. The system according to claim 8 for managing on-demand emailstorage, wherein said criteria comprises at least one from among anemail identifier, a domain name, an email size, and a keyword.
 10. Thesystem according to claim 6 for managing on-demand email storage,further comprising: means for charging said intended recipient for saidallocated on-demand storage space.
 11. A computer program product,residing on a computer readable medium, for managing on-demand emailstorage, said computer program product comprising: means for enablingreceipt of an email for an intended recipient at an email serviceprovider, wherein said email service provider allocates a predeterminedstorage space to said intended recipient; means for determining whethersaid predetermined storage space has sufficient capacity for storage ofsaid email; means, responsive to determining said predetermined storagespace has insufficient capacity for storage of said email, forcontrolling allocation of on-demand storage space to said intendedrecipient; and means for enabling storage of said email in saidallocated on-demand storage space, such that said email is stored,rather than discarded, when said predetermined storage space reachesfull capacity.
 12. The computer program product according to claim 111for managing on-demand email storage, wherein said means for controllingallocation of on-demand storage space to said intended recipient furthercomprises: means for determining, responsive to determining saidpredetermined storage space has insufficient capacity for storage ofsaid email, whether said intended recipient is registered for saidon-demand storage space; means, responsive to determining said intendedrecipient is registered for said on-demand storage space, forcontrolling allocation of said on-demand storage space to said intendedrecipient; and means, responsive to determining said intended recipientis not registered for said on-demand storage space, for discarding saidemail.
 13. The computer program product according to claim 111 formanaging on-demand email storage, wherein said means for controllingallocation of on-demand storage space to said intended recipient furthercomprises: means for determining, responsive to determining saidpredetermined storage space has insufficient capacity for storage ofsaid email, whether said email matches with criteria set by saidintended recipient for addition of said on-demand storage space; means,responsive to said email matching said criteria, for controllingallocation of said on-demand storage space to said intended recipient;and means, responsive to said email not matching said criteria, fordiscarding said email.
 14. The computer program product according toclaim 11 for managing on-demand email storage, further comprising: meansfor charging said intended recipient for said allocated on-demandstorage space.
 15. A method for enabling email subscribers to access alldesired emails received at a mail service provider, comprising:prompting an email subscriber at a user interface to select an on-demandstorage option for storage of email by a mail service provider when astorage space allocated to said email subscriber reaches capacity;responsive to said email subscriber selecting said on-demand storageoption, prompting said email subscriber at said user interface to selectcriteria for emails to be stored in on-demand storage; and storing saidselection of said on-demand storage option and said criteria in saidemail subscriber profile at said mail service provider, such that whenan email is received by said mail service provider for said emailsubscriber and said storage space allocated to said email subscriber isfull, then said mail service provider determines whether to allocatesaid on-demand storage for said email.
 16. A system for enabling emailsubscribers to access all desired emails received at a mail serviceprovider, comprising: a user interface for prompting an email subscriberto select an on-demand storage option for storage of email by a mailservice provider when a storage space allocated to said email subscriberreaches capacity; means, responsive to said email subscriber selectingsaid on-demand storage option, for prompting said email subscriber atsaid user interface to select criteria for emails to be stored inon-demand storage; and means for storing said selection of saidon-demand storage option and said criteria in said email subscriberprofile at said mail service provider, such that when an email isreceived by said mail service provider for said email subscriber andsaid storage space allocated to said email subscriber is full, then saidmail service provider determines whether to allocate said on-demandstorage for said email.
 17. A computer program product, residing on acomputer readable medium, for enabling email subscribers to access alldesired emails received at a mail service provider, comprising: meansfor prompting an email subscriber via a user interface to select anon-demand storage option for storage of email by a mail service providerwhen a storage space allocated to said email subscriber reachescapacity; means, responsive to said email subscriber selecting saidon-demand storage option, for prompting said email subscriber via saiduser interface to select criteria for emails to be stored in on-demandstorage; and means for storing said selection of said on-demand storageoption and said criteria in said email subscriber profile at said mailservice provider, such that when an email is received by said mailservice provider for said email subscriber and said storage spaceallocated to said email subscriber is full, then said mail serviceprovider determines whether to allocate said on-demand storage for saidemail.